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EXOSAT measurement of the spectrum of Markarian 382.

Singh, K. P.; Rao, A. R.; Vahia, M. N.

The 0.1-10 keV X-ray spectrum of a Seyfert galaxy known as Markarian 382 (Mkn 382) is presented based on observations with the EXOSAT. The energy index (α) for the power-law X-ray continuum of Mkn 382 is measured to be 1.2^+0.16^_0.14_ which is higher than the canonical value found for the Seyfert galaxies. There is no evidence for intrinsic absor…

The treatment of HIPPARCOS observations of some peculiar double stars - Anomalous cases

Pannunzio, R.; Lattanzi, M. G.; Morbidelli, R. +2 more

We present an investigation on a few different types of double stars which, when observed by the Hipparcos satellite, will probably produce anomalous signals. Specifically, for these objects the automatic data reduction chain set up by the FAST Consortium will usually give inconsistent results. Thus, some new mathematical models have been consider…

X-Ray Continuum with an Iron Emission Line from the Radio-Quiet Quasar PHL 909

Ghosh, K. K.; Soundararajaperumal, S.

Results of the spectral analysis of the X-ray (0.1 - 10 keV) spectrum of the radio-quiet quasar, PHL 909, are presented. A spectrum of this quasar which was observed on 1984/349, was obtained from the EXOSAT archives. Different models were used to fit the ME and LE+ME data. Fit parameters to the ME data show a steep spectral index for this quasar …

The Ulysses space mission.

Poletto, G.; Noci, G.; Monsignori Fossi, B. C.

The authors describe briefly the collaborative ESA-NASA Ulysses mission which will provide, for the first time in the history of the solar-system exploration, in situ observations of the heliosphere over a broad range of heliographic latitudes. Launched on October 6, 1990, Ulysses has been injected in a high-inclination orbit by means of a gravity…

Optical Properties of Cool Stars Discovered by EXOSAT

Tagliaferri, G.; Pasquini, L.; Pallavicini, R. +3 more

A study of the IUE ultraviolet spectrum of KHI 02 Orionis.

Sapar, L.; Sapar, A.

Ephemerides of the 48 HIPPARCOS minor planets for the year 1992

Bec-Borsenberger, A.

To be observed by Hipparcos, the position of each object has to be known with an accuracy of 1 arcsecond and its magnitude with an accuracy of 0.5 mag. Therefore, the orbital elements of the 48 selected minor planets of the Hipparcos mission, have been improved in order to extrapolate their ephemerides with the accuracy required. Updated ephemerid…

Detection of Rs-Canum Type Systems by Doublet 2800 MGII

Gurzadian, G. A.; Cholakian, V. G.

The problem of the detection or discovery of RS CVn-type close binary systems with the aid of the magnesium emission doublet 2800 MgII is discussed. On the example of a star, HD 102077, the possibility of such an approach is shown. The determining factor is the magnitude of the measureless parameterR(MgII), that is, the relative power of the magne…

Ulysses Spacecraft Rendezvous with Jupiter

Barbosa, David D.; Kivelson, Margaret G.

Leaving Jupiter, Ulysses Heads for the Sun's South Pole

Appenzeller, Tim